Safe Laser technology
At its core, the Safe Laser technology stands apart because of its special diffuser surface that transforms the hazardous parallel beam of the laser in such a way that it becomes completely harmless to the human eye. The essence of its optical system remains a diffuser lens that “unlocks” the parallel laser beam before a secondary diffuser surface ensures that the lens of the eye cannot refocus it to dangerous levels, so it can't cause injury to the retina and the optic nerves.
All Safe Laser devices have this unique laser light source, which emits polarized, coherent and monochromatic light (like other lasers), but its light does not exhibit parallel rays and cannot be focused optically into a very bright light spot in contrast to the conventional lasers.
SL500 Infra = "Class I" laser device,
SL150 =“Class 2” laser device,
according to the IEC 60825-1:2014, Safety of laser products. Part 1: Equipment classification and requirements
Measurement and Classification – Made by Wigner Research Centre for Physics Optical Laboratory (former Central Research Institute for Physics) – Research Institute for Solid State Physics.
There is no need for a protective device – such as goggles – if an optical device (such as a convergent lens) is not inserted.